The disclosure relates to lighting systems and more particularly to communications apparatus and techniques for communicating with ballasts or drivers through power connections in a lighting system. Remote lighting control is desirable, and in particular, control of electronic ballasts and/or LED drivers via the power line connections allows improved functionality without additional control wiring. Power line communications (PLC) circuits have been in existence for many years, in which a modulated carrier signal is transmitted through the power wiring to which a lighting system ballast is connected. These existing circuits, however, often require filter trapping to confine the signal to the targeted ballasts or controllable devices, and the ballast must have a receiver to interpret signals that are superimposed on the power line. Accordingly, conventional power line communications systems are inflexible and expensive. Triac modulation of the power line voltage by modulation of the phase angle has also been discussed but this can have severe compatibility issues with ballasts that are incapable of absorbing pulsed current from the triac. Thus, there remains a need for improved communications systems to mitigate or avoid these problems of power line communications filters and triac incompatibility.